Created attachment 359564 [details]
Description of problem:
Since bug 206806 was fixed in 2.6.18-98.el5 the ia64 kernel implements the pselect() and ppoll() syscalls. glibc is still not using them as of RHEL-5.3 and instead emulates it with the racy equivalent.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Compile and run test program attached.
Pending signals are caught at sigprocmask() time and then select() may block forever, in the racy pselect() "equivalent".
Use the actual pselect() syscall that will then return pending signals and not block forever.
x86_64 and ia64 straces of the test program will be attached.
Created attachment 359565 [details]
Correct x86_64 pselect() call.
Created attachment 359566 [details]
Incorrect ia64 pselect() emulated by glibc.
This is a bug in kernel-headers, it needs to define the syscalls.
glibc then just needs to be rebuilt against the fixed kernel-headers and it will magically pick up the syscalls.
Created attachment 361518 [details]
RHEL5 fix for this issue
Patch that resolves this issue.
Tested by doing
1. compile reproducer with existing glibc. Test fails.
2. apply patch to tree, and install kernel-headers.
3. rebuild glibc rpms
4. reinstall glibc rpms
5. compile reproducer. Test succeeds:
[root@altix4 tmp]# ./doit
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release. Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products. This request is not yet committed for inclusion in an Update
You can download this test kernel from http://people.redhat.com/dzickus/el5
Please do NOT transition this bugzilla state to VERIFIED until our QE team
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to provide a comment indicating that this fix has been verified.
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Clearing stale NEEDINFO request.
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
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